What open source multivariate or a/b testing frameworks or libraries are available?

Question

Google Website Optimizer http://www.google.com/websiteoptimizer and Visual Website Optimizer http://visualwebsiteoptimizer.com/ both allow me to run experiments for individual sections of content on web pages. But, what libraries or frameworks are available for running tests on things other than snippets of HTML?

In other words, are there open source projects which provide the underpinning logic and calculations required to build my own multivariate tests?

One such library is ABingo http://www.bingocardcreator.com/abingo in Ruby. But, what other libraries/frameworks are available?

Answer 1

There are couple of resources listed on my blog here:

http://www.wingify.com/conversion-blog/15-free-ab-split-testing-resources/